COMPOSITION AND ORIGIN OF POSTGLACIAL BOTTOM SEDIMENTS FROM CENTRAL AND NORTHEASTERN PARTS OF THE BARENTS SEA (RUSSIAN SECTOR)

The lighology of postglacial bottom sediments are studied in cores from central and north-eastern part of the Barents Sea (25 and 28 cruises of R/V “Academic Nikolai Strakhov” in 2007 and 2011 respectively). Petrographic and chemical composition of modern and late Quaternary sediments from the Fedynskii swell area and the southern rim of the Franz Josef Land were examined. The study revealed sources of clastic material and permitted to estimate their influence on the various stages of post glacial sedimentation. At the end of Late Pleistocene (the initial phase of the ice cover degradation) granitoid rocks of the Kola peninsula are considered to be the main source of clastics in the Fedynskii swell area, while volcanic-sedimentary strata that compose FJL governed sedimentation in the North- East. Sedimentation was accompanied by intense ice-rafting that resulted in mixing of clastics from both sources. Ate the Late Pleistocene to Holocene boundary and later in Holocene the main source of clastic material remained unchanged in the central part of the sea. In the North-East sedimentation was controlled by recycling of previously accumulated deposits. Ice-rafting had no significant values such as at early deglaciation phase. In the case of poor faunal characterization and/or the absence of radiocarbon data petrographic and geochemical study can be used for stratification of the Barents sea bottom sediments.

sediments, sedimentogenesis, deglaciation, ice-rafting